1. Field of the Invention
The present invention relates to improvements in apparatus for brewing hot beverages in brewing machines including coin operated vending machines and the like as well as a method of operating such apparatus in a manner which increases the utility and versatility of the machine. The apparatus is intended for use in brewing and dispensing espresso coffee.
2. Description of the Prior Art
Coin operated vending machines for dispensing a wide variety of beverages, including hot beverages which are mixed on an individual basis, are well known in the art. With the advent of sophisticated electronics and microprocessors in particular, such vending machines are capable of quite complex functions such as making selections from an array of available beverages, selecting separate ingredients and the amounts of each to be dispensed, e.g. cream, sugar and other flavorings. Additionally, the various functions of the machine in matching deposited monetary amounts with multiple selections made and performing certain diagnostic tests for machine malfunction and/or status are well understood. An example of such electronic controls for coin operated beverage machines may be found in U.S. Pat. No. 4,597,506 to David Eglise et al. Various improvements in brewing apparatus for compacting and charging the compacted ground coffee with hot water under pressure are also available in the art, see U.S. Pat. No. 5,103,716 to Per W. Mikkelsen as an example.
The present apparatus deals with improvements in existing coin operated vending machines of the type manufactured and marketed by Ducale Macchine da Caffe--di Sandei Ugo & C.s.n.c., Parma, Italy. The brewing unit is of the foaming general type disclosed in Italian Patent No. 46851A/84 issued to Ducale Macchine da Caffe; Italian Patent No. 33657A/69 issued to Ugo Sandei and Altobano Prampolini; and Italian Patent No. 46027A/75 issued to Ugo Sandei and Altobano Prampolini, respectively. The brewing mechanism in these prior patents has been improved by the present invention for greater efficiency and better overall performance of the machine.